A Report on the Use of SimplyThick for Infants

The Food and Drug Administration issued a caution last year that SimplyThick, a thickening agency, should not be fed to premature infants because it may cause necrotizing enterocolitis (NEC), a life-threatening condition that damages intestinal tissue. It was reported that experts can’t say exactly how the product may be linked to NEC. But, it appears that a number of children have died after receiving SimplyThick. An FDA investigation of 84 cases, published in The Journal of Pediatrics in 2012, found a “distinct illness pattern” in 22 instances that suggested a “possible link” between SimplyThick and NEC. Seven deaths were cited and 14 infants required surgery.

Last September, after more adverse events were reported, the FDA warned that the thickener should not be given to any infants. But the fact that SimplyThick was widely used at all in neonatal intensive care units has resulted in a number of lawsuits. Questions have also been raised about regulatory oversight of food additives for infants. SimplyThick is made from xanthan gum, a widely-used food additive on the FDA’s list of substances “generally recognized as safe.” But since SimplyThick is classified as a food, the FDA did not assess it for safety.

John Holahan, president of SimplyThick, which is based in St. Louis, has acknowledged that the company marketed the product to speech language pathologists who in turn recommended it to infants. The product’s patent touted its effectiveness in breast milk. Interestingly, Mr. Holahan made this observation:

There was no need to conduct studies, as the use of thickeners overall was already well established. In addition, the safety of xanthan gum was already well established.

Since 2001, SimplyThick has been widely used by adults with swallowing difficulties. A liquid thickened to about the consistency of honey allows the drinker more time to close his airway and prevent aspiration. It was reported that doctors in newborn intensive care units often ask non-physician colleagues like speech pathologists to determine whether an infant has a swallowing problem. Those auxiliary feeding specialists often recommended SimplyThick for neonates with swallowing troubles or acid reflux.

The thickener became popular because it was easy to mix, could be used with breast milk, and maintained its consistency, unlike alternatives like rice cereal. Dr. Steven Abrams, a neonatologist at Texas Children’s Hospital in Houston, told the New York Times:

It was word of mouth, then neonatologists got used to using it. It became adopted. At any given time, several babies in our nursery — and in any neonatal unit — would be on it.

But in early 2011, Dr. Benson Silverman, the director of the FDA’s infant formula section, was alerted to an online forum where doctors had reported 15 cases of NEC among infants given SimplyThick. In May, the agency issued its first warning about its use in babies. Dr. Silverman, in explaining the FDA’s position, had this to say:

We can only do something with the information we are provided with. If information is not provided, how would we know?

It should be noted that most infants who took SimplyThick did not become sick. Also, NEC is not uncommon in premature infants. But most infants who develop NEC do so while still in the hospital. Some premature infants given SimplyThick developed NEC later than usual, a few after they went home, a pattern the FDA found unusually worrisome. Even now it is not known how the thickener might have contributed to the infant deaths. One possibility is that xanthan gum itself is not suitable for the fragile digestive systems of newborns. The intestines of premature babies are “much more likely to have bacterial overgrowth” than adults, according to Dr. Jeffrey Pietz, the chief of newborn medicine at Children’s Hospital Central California in Madera. Dr. Pietz observed:

You try not to put anything in a baby’s intestine that’s not natural. If you do you’ve got to have a good reason.

A second possibility is that batches of the thickener were contaminated with harmful bacteria. In late May 2011, the FDA inspected the plants that make SimplyThick and found violations at one in Stone Mountain, Ga., including a failure to “thermally process” the product to destroy bacteria of a “public health significance.” The company, Thermo Pac, voluntarily withdrew certain batches. But it appears some children may have ingested potentially contaminated batches.

The authors of the FDA report theorized that the infants’ intestinal membranes could have been damaged by bacteria breaking down the xanthan gum into too many toxic byproducts. Dr. Qing Yang, a neonatologist at Wake Forest University, is a co-author of a case series in the Journal of Perinatology about three premature infants who took SimplyThick, developed NEC and were treated. This paper states that NEC was “most likely caused by the stimulation of the immature gut by xanthan gum.” Dr. Yang said she only belatedly realized “there’s a lack of data” on xanthan gum’s use in preemies. She added that the lesson learned “is not to be totally dependent on the speech pathologist.” I suspect there will be much more said by the medical community on this subject. We will continue to monitor the situation.